Carbon aerogels for supercapacitors and method of manufacturing the same

a supercapacitor and aerogel technology, applied in chemical/physical processes, non-conductive materials with dispersed conductive materials, synthetic resin layered products, etc., can solve the problem that existing methods need an additional activation step to obtain high activity, and achieve the effect of improving time efficiency and energy efficiency, simplifying the overall process, and shortening the time period

Inactive Publication Date: 2013-07-09
KOREA INST OF SCI & TECH
View PDF17 Cites 58 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0005]According to a preferred embodiment, the method for preparing carbon aerogels includes dissolving organic starting materials for preparing organic aerogels in an organic solvent and adequately adjusting pH of the resultant solution to form gels at room temperature in a short period of time. Therefore, the method provides improved time efficiency and energy efficiency as compared to existing methods for preparing gels. Additionally, the method allows supercritical drying while avoiding a need for an additional solvent substitution step by using a solvent easily miscible with carbon dioxide, thereby simplifying the overall process. Further, the method enables preparation of carbon aerogels having a high specific surface area and high capacitance even in the absence of an additional activation step. The carbon aerogels can be applied to various applications, including electrode materials for supercapacitors, electrode materials for seawater desalination and deionization-based water purification, electrode materials for secondary batteries and fuel cells, adsorption and removal of harmful substances using a large specific surface area, catalyst carriers, hydrogen storage materials, and the like.

Problems solved by technology

Additionally, such existing methods need an additional activation step to obtain high activity.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Carbon aerogels for supercapacitors and method of manufacturing the same
  • Carbon aerogels for supercapacitors and method of manufacturing the same

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0019]First, 1.6378 g of phloroglucinol is dissolved in 58.6 mL of ethanol. Next, nitric acid is added thereto in a molar ratio of 1 / 0.001 based on phloroglucinol, and the reaction mixture is sealed and agitated for 30 minutes at room temperature. Then, furfural is added in a molar ratio of 1 / 3 based on phloroglucinol, and the reaction mixture is sealed and agitated at room temperature to carry out a reaction. After gels are formed, agitation is terminated and the gels are aged at room temperature for 4 days. The aged gels are subjected to supercritical drying under 170 atm at 70° C. to form organic aerogels. Finally, the organic aerogels are heat treated in an electric furnace, through which helium flows, at a heating rate of 1° C. / min to 800° C. so that the organic aerogels are converted into carbon aerogels.

example 2

[0021]First, 1.6378 g of phloroglucinol is dissolved in 58.6 mL of ethanol. Next, furfural is added thereto in a molar ratio of 1 / 3 based on phloroglucinol. Then, the reaction mixture is sealed and agitated at room temperature to carry out a reaction. After gels are formed, agitation is terminated and the gels are aged at room temperature for 3 days. The aged gels are subjected to supercritical drying under 170 atm at 70° C. to form organic aerogels. Finally, the organic aerogels are heat treated in an electric furnace, through which helium flows, at a heating rate of 1° C. / min to 800° C. so that the organic aerogels are converted into carbon aerogels.

example 3

[0023]First, 1.6378 g of phloroglucinol is dissolved in 58.6 mL of ethanol. Next, potassium hydroxide is added thereto in a molar ratio of 1 / 0.01 based on phloroglucinol. The reaction mixture is sealed and agitated at room temperature for 30 minutes. Then, furfural is added thereto in a molar ratio of 1 / 3 based on phloroglucinol, and the reaction mixture is sealed and agitated at room temperature to carry out a reaction. After gels are formed, agitation is terminated and the gels are aged at room temperature for 3 days. The aged gels are subjected to supercritical drying under 170 atm at 70° C. to form organic aerogels. Finally, the organic aerogels are heat treated in an electric furnace, through which helium flows, at a heating rate of 1° C. / min to 800° C. so that the organic aerogels are converted into carbon aerogels.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
temperatureaaaaaaaaaa
temperatureaaaaaaaaaa
temperatureaaaaaaaaaa
Login to view more

Abstract

A method for preparing carbon aerogels and carbon aerogels obtained therefrom are disclosed. The method for preparing carbon aerogels comprises: mixing organic starting materials including phloroglucinol and furfural with a solvent capable of dissolving the organic materials in a predetermined ratio to form a sol solution; adjusting pH of the sol solution adequately by using an acidic or basic catalyst, gelling the sol solution at room temperature under atmospheric pressure, and aging the resultant gels; substituting the solvent in thus obtained gels with liquid carbon dioxide, followed by drying in a supercritical state, to form organic aerogels; and pyrolyzing the organic aerogels in an electric furnace under inert atmosphere to obtain carbon aerogels. Particularly, the gels are formed at room temperature in a short period of time by adequately adjusting pH of the sol solution. Therefore, the method provides improved time efficiency and energy efficiency as compared to existing methods for preparing gels. Additionally, the method allows supercritical drying while avoiding a need for an additional solvent substitution, thereby simplifying the overall process. Further, the method enables preparation of carbon aerogels for supercapacitors having a high specific surface area and high capacitance even in the absence of additional activation step.

Description

FIELD OF THE INVENTION[0001]Example embodiments disclosed herein relate to a method for preparing carbon aerogels for supercapacitors and carbon aerogels obtained therefrom.BACKGROUND OF THE INVENTION[0002]Carbon aerogels are porous materials with high porosity. Due to their high electrical conductivity and large specific surface area, carbon aerogels may be used in high-performance electrode materials, energy storage devices, harmful substance adsorbents, capacitive deionization-based water purification processes, seawater desalination processes, ion exchange-based waste water treatment processes, and the like. Such carbon aerogels may be obtained from heat treatment of organic aerogels. In general, starting materials for preparing the organic aerogels include resorcinol-formaldehyde, polyacrylonitrile (PAN) and polyurethane (PU). In the case of most existing organic aerogels, an adequate amount of catalyst is added to aqueous solution of the above organic materials, followed by he...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Patents(United States)
IPC IPC(8): H01B1/04H01G11/32H01G11/34
CPCB01J13/0091C01B31/02C04B35/524C04B35/62655C04B38/00H01G11/34C04B35/52H01G11/32Y02E60/13C01B32/05Y02P20/10C01B32/00
Inventor SUH, DONG JINPARK, TAE JINSUH, YOUNG-WOONGYOON, YOUNG HYUNKIM, HYUN-JOONG
Owner KOREA INST OF SCI & TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products